First Battle of St. Albans

The First Battle of St. Albans was fought on 22 May 1455 between the armies of the House of York and the House of Lancaster at the start of the Wars of the Roses. Duke Richard of York and the allied Neville family defeated the royal army under the Duke of Somerset (who was killed) and captured King Henry VI of England, who was forced to name Richard Lord Protector once more.

Background
In 1453, with the English defeat in the Hundred Years' War, King Henry VI of England suffered a mental breakdown and became unresponsive, leading to the King losing the remainder of his political power. Edmund Beaufort, 1st Duke of Somerset became one of the most powerful men at the English court, backing the Percy family in its renewed feud with the Neville family in northern England. Duke Richard of York, a sworn enemy of Somerset, allied himself with the Nevilles, and, by 1454, Richard had enough backing to become Lord Protector and appoint his supporters to high offices; he also had Somerset imprisoned. By 1455, the King had recovered, and Queen Margaret of Anjou managed to influence the King once again, exiling Richard and rolling back his decisions. Richard responded by raising an army and marching on London, leading to war with Somerset and his supporters.

Battle
Henry knew that he would receive no support in London, so he and a 2,000-strong army moved north to St. Albans to confront the Yorkist army. The 5,000+-strong Yorkist army under Richard met the Lancastrians in battle, and, when the King refused to surrender Somerset, the Yorkists attacked. Humphrey Stafford, 1st Duke of Buckingham's Lancastrian troops guarded the gates on Sopwell and Shropshire Lanes while the King was in the market square; Richard's army drew up on a field behind the gardens of Holywell Street, the Market Square, and St. Peter's Square in the east. At 10:00 AM, Warwick, Salisbury, and York simultaneously attacked the Lancastrians at the gates, achieving an initially successful surprise attack. However, the Lancastrians soon rushed in reinforcements to defend the strongpoints. The fighting took place on narrow streets, where the battle bogged down into a stalemate. The stalemate was broken when Warwick withdrew from the main battle, flanked the Lancastrian rear, smashed the Lancastrian rearguard near the Market Square gardens, and forced the defenders at the gates to withdraw to the Market Square. The Yorkists now advanced on all fronts, and Yorkish archers continually showered the remaining Lancastrians with missiles, killing Somerset and Buckingham. King Henry was captured by the Yorkists and taken back to London, where the Duke of York was named Lord Protector.

Aftermath
By that time, Queen Margaret had given birth to Edward, Prince of Wales and become the leader of the Lancastrian faction. From 1456 to 1459, the only fighting was done between the Nevilles and Percys, as both sides were equally shocked by the battle. King Henry sought to mediate between the Yorkists and Lancastrians, but the suspicions still proved strong, leading to the Battle of Ludford Bridge in 1459.